Gymnocarpium jessoense(Koidz.) Koidz.

Asian oakfern

WFO wfo-0001111179 Accepted WFO 2026-06 8 photographs CC BY

Plate 1 figs. a–h · 4 observations

This species has been photographed under an open licence only 4 times, so some figures below are different views of the same plant, taken on the same day, rather than different individuals. They are usually different parts of it: the leaf, the flower, the bark.

Gymnocarpium jessoense, photographed by Dmitry Kulakov
fig. a Dmitry Kulakov, CC BY 4.0 / 2021-06-14 / obs. 136477687
Gymnocarpium jessoense, photographed by Dmitry Kulakov
fig. b Dmitry Kulakov, CC BY 4.0 / obs. 136477690
Gymnocarpium jessoense, photographed by Юлия
fig. c Юлия, CC BY 4.0 / obs. 134308168
Gymnocarpium jessoense, photographed by Евгений Егорейченков
fig. d Евгений Егорейченков, CC BY 4.0 / obs. 190835390
Gymnocarpium jessoense, photographed by Юлия
fig. e Юлия, CC BY 4.0 / obs. 139273556
Gymnocarpium jessoense, photographed by Юлия
fig. f Юлия, CC BY 4.0 / obs. 139273502
Gymnocarpium jessoense, photographed by Юлия
fig. g Юлия, CC BY 4.0 / obs. 134308120
Gymnocarpium jessoense, photographed by Юлия
fig. h Юлия, CC BY 4.0 / obs. 134308194

Every figure is a research-grade observation under CC0, CC BY or CC BY-SA, rehosted with the photographer’s name, the licence and the observation it came from. Photographs under a NonCommercial licence are excluded from this site and are never stored, which costs us a great many pictures and is not negotiable.

Native range 30 botanical countries

Regions where Gymnocarpium jessoense is native: Afghanistan, Altay, Amur, Buryatiya, China North-Central, China South-Central, China Southeast, Chita, Inner Mongolia, Irkutsk, Japan, Kamchatka, Kazakhstan, Khabarovsk, Korea, Krasnoyarsk, Magadan, Manchuria, Primorye, Qinghai, Sakhalin, Tibet, Tuva, West Siberia, Xinjiang, Yakutiya, East Himalaya, Nepal, Pakistan, West Himalaya AfghanistanAltayAmurBuryatiyaChina North-CentralChina South-CentralChina SoutheastChitaInner MongoliaIrkutskJapanKamchatkaKazakhstanKhabarovskKrasnoyarskMagadanManchuriaPrimoryeQinghaiSakhalinTibetTuvaWest SiberiaXinjiangYakutiyaEast HimalayaNepalPakistanWest Himalaya Korea
Native distribution of Gymnocarpium jessoense, after Kew’s World Checklist of Vascular Plants. Introduced, extinct and doubtful records are excluded, so this is where the plant is from, not everywhere it now grows. Regions too small to draw at this scale are marked with a dot.
RegionTDWG codeContinent
Afghanistan AFG ASIA-TEMPERATE
Altay ALT
Amur AMU
Buryatiya BRY
China North-Central CHN
China South-Central CHC
China Southeast CHS
Chita CTA
Inner Mongolia CHI
Irkutsk IRK
Japan JAP
Kamchatka KAM
Kazakhstan KAZ
Khabarovsk KHA
Korea KOR
Krasnoyarsk KRA
Magadan MAG
Manchuria CHM
Primorye PRM
Qinghai CHQ
Sakhalin SAK
Tibet CHT
Tuva TVA
West Siberia WSB
Xinjiang CHX
Yakutiya YAK
East Himalaya EHM ASIA-TROPICAL
Nepal NEP
Pakistan PAK
West Himalaya WHM

Region boundaries approximated from Natural Earth (public domain) and mapped to TDWG World Geographical Scheme for Recording Plant Distributions (WGSRPD) level-3 botanical countries (Brummitt 2001). Indicative, not the official WGSRPD geometry.

Where it actually grows measured, from 172 observations

Condition 5th percentile Median 95th percentile
Coldest month, mean daily low -35.5 °C -28.3 °C -17.4 °C
Warmest month, mean daily high 14.4 °C 19.3 °C 24.2 °C
Annual rainfall 412 mm 786 mm 1,263 mm
Rainfall in the driest quarter 14 mm 59 mm 184 mm

It is found where winters are arctic. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 172 research-grade observations of Gymnocarpium jessoense that carry a coordinate, and this is the range those places actually span. The 5th and 95th percentiles are used rather than the minimum and maximum, because a single cultivated specimen in a heated conservatory should not widen a tropical plant's range to the Arctic.

This is not a hardiness zone. A USDA zone is the average annual extreme minimum temperature. The figure above is the mean daily minimum of the coldest month, which is a different quantity and is typically far warmer. Reading one as the other would place a plant several zones too warm, so we do not publish a hardiness zone, because we do not have one.

Also published as 11 synonyms

A synonym is not an error. It is a record of botanists disagreeing, in print, about where this plant belongs. Each of these was somebody’s considered answer.

  • Aspidium dryopteris var. longulum Christ
  • Carpogymnia jessoensis (Koidz.) Á.Löve & D.Löve
  • Dryopteris jessoensis Koidz.
  • Dryopteris linnaeana var. jessoensis (Koidz.) C.Chr.
  • Gymnocarpium longulum (Christ) Kitag.
  • Gymnocarpium robertianum subsp. longulum (Christ) Toyok.
  • Gymnocarpium robertianum var. longulum (Christ) H.Itô ex Nakai
  • Gymnocarpium tenuipes Pojark. & Shmakov
  • Lastrea jessoensis Akas.
  • Lastrea jessoensis (Koidz.) Akasawa
  • Lastrea robertiana var. longula (Christ) Ohwi

Sourcesevery claim on this page

  1. World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
  2. iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.
  3. Wikidata. common name (P1843), joined on the World Flora Online identifier (P7715). CC0. Retrieved 2026-07-13.
  4. Kew, World Checklist of Vascular Plants (WCVP v16). native distribution by TDWG level-3 botanical country, and life form. CC BY 3.0. Retrieved 2026-06-04.

We publish what we can source and we say so when we cannot. This page has no care advice and no toxicity claim, because we do not yet have those from a source we can cite.